[Java] Reduce copying when generating codecs.

Author: mjpt777

sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/java/JavaGenerator.java

@@ -207,13 +207,13 @@ private void generateEncoder(
  generateAnnotations(indent, className, groups, out, 0, this::encoderName);
  out.append(generateDeclaration(className, implementsString, msgToken));
  out.append(generateEncoderFlyweightCode(className, msgToken));
- out.append(generateEncoderFields(className, fields, indent));
 
  final StringBuilder sb = new StringBuilder();
+ generateEncoderFields(sb, className, fields, indent);
  generateEncoderGroups(sb, className, groups, indent, false);
- out.append(sb);
+ generateEncoderVarData(sb, className, varData, indent);
 
- out.append(generateEncoderVarData(className, varData, indent));
+ out.append(sb);
 
  out.append(generateEncoderDisplay(formatClassName(decoderName(msgToken.name())), indent));
 
@@ -238,14 +238,13 @@ private void generateDecoder(
  generateAnnotations(indent, className, groups, out, 0, this::decoderName);
  out.append(generateDeclaration(className, implementsString, msgToken));
  out.append(generateDecoderFlyweightCode(className, msgToken));
- out.append(generateDecoderFields(fields, indent));
 
  final StringBuilder sb = new StringBuilder();
+ generateDecoderFields(sb, fields, indent);
  generateDecoderGroups(sb, className, groups, indent, false);
+ generateDecoderVarData(sb, varData, indent);
  out.append(sb);
 
- out.append(generateDecoderVarData(varData, indent));
-
  out.append(generateDecoderDisplay(msgToken.name(), fields, groups, varData, indent));
 
  out.append("}\n");
@@ -283,13 +282,13 @@ private void generateDecoderGroups(
  final List<Token> varData = new ArrayList<>();
  i = collectVarData(tokens, i, varData);
 
- sb.append(generateGroupDecoderProperty(groupName, groupToken, indent, isSubGroup));
+ generateGroupDecoderProperty(sb, groupName, groupToken, indent, isSubGroup);
  generateAnnotations(indent + INDENT, groupName, tokens, sb, groupIndex + 1, this::decoderName);
  generateGroupDecoderClassHeader(sb, groupName, outerClassName, tokens, groups, groupIndex, indent + INDENT);
 
- sb.append(generateDecoderFields(fields, indent + INDENT));
+ generateDecoderFields(sb, fields, indent + INDENT);
  generateDecoderGroups(sb, outerClassName, groups, indent + INDENT, true);
- sb.append(generateDecoderVarData(varData, indent + INDENT));
+ generateDecoderVarData(sb, varData, indent + INDENT);
 
  appendGroupInstanceDecoderDisplay(sb, fields, groups, varData, indent + INDENT);
 
@@ -329,13 +328,13 @@ private void generateEncoderGroups(
  final List<Token> varData = new ArrayList<>();
  i = collectVarData(tokens, i, varData);
 
- sb.append(generateGroupEncoderProperty(groupName, groupToken, indent, isSubGroup));
+ generateGroupEncoderProperty(sb, groupName, groupToken, indent, isSubGroup);
  generateAnnotations(indent + INDENT, groupClassName, tokens, sb, groupIndex + 1, this::encoderName);
  generateGroupEncoderClassHeader(sb, groupName, outerClassName, tokens, groups, groupIndex, indent + INDENT);
 
- sb.append(generateEncoderFields(groupClassName, fields, indent + INDENT));
+ generateEncoderFields(sb, groupClassName, fields, indent + INDENT);
  generateEncoderGroups(sb, outerClassName, groups, indent + INDENT, true);
- sb.append(generateEncoderVarData(groupClassName, varData, indent + INDENT));
+ generateEncoderVarData(sb, groupClassName, varData, indent + INDENT);
 
  sb.append(indent).append(" }\n");
  }
@@ -549,19 +548,18 @@ private void generateGroupDecoderClassDeclaration(
  {
  final String className = formatClassName(groupName);
 
+ generateTypeJavadoc(sb, indent, groupToken);
  sb.append(String.format("\n" +
- "%1$s" +
- indent + "public static class %2$s\n" +
- indent + " implements Iterable<%2$s>, java.util.Iterator<%2$s>\n" +
+ indent + "public static class %1$s\n" +
+ indent + " implements Iterable<%1$s>, java.util.Iterator<%1$s>\n" +
  indent + "{\n" +
- indent + " public static final int HEADER_SIZE = %3$d;\n" +
- indent + " private final %4$s parentMessage;\n" +
- indent + " private %5$s buffer;\n" +
+ indent + " public static final int HEADER_SIZE = %2$d;\n" +
+ indent + " private final %3$s parentMessage;\n" +
+ indent + " private %4$s buffer;\n" +
  indent + " private int count;\n" +
  indent + " private int index;\n" +
  indent + " private int offset;\n" +
  indent + " private int blockLength;\n",
- generateTypeJavadoc(indent, groupToken),
  className,
  dimensionHeaderSize,
  parentMessageClassName,
@@ -604,17 +602,16 @@ private void generateGroupEncoderClassDeclaration(
  {
  final String className = formatClassName(encoderName(groupName));
 
+ generateTypeJavadoc(sb, indent, groupToken);
  sb.append(String.format("\n" +
- "%1$s" +
- indent + "public static class %2$s\n" +
+ indent + "public static class %1$s\n" +
  indent + "{\n" +
- indent + " public static final int HEADER_SIZE = %3$d;\n" +
- indent + " private final %4$s parentMessage;\n" +
- indent + " private %5$s buffer;\n" +
+ indent + " public static final int HEADER_SIZE = %2$d;\n" +
+ indent + " private final %3$s parentMessage;\n" +
+ indent + " private %4$s buffer;\n" +
  indent + " private int count;\n" +
  indent + " private int index;\n" +
  indent + " private int offset;\n",
- generateTypeJavadoc(indent, groupToken),
  className,
  dimensionHeaderSize,
  parentMessageClassName,
@@ -646,10 +643,13 @@ private void generateGroupEncoderClassDeclaration(
  sb.append(indent).append(" }\n\n");
  }
 
- private static CharSequence generateGroupDecoderProperty(
- final String groupName, final Token token, final String indent, final boolean isSubGroup)
+ private static void generateGroupDecoderProperty(
+ final StringBuilder sb,
+ final String groupName,
+ final Token token,
+ final String indent,
+ final boolean isSubGroup)
  {
- final StringBuilder sb = new StringBuilder();
  final String className = formatClassName(groupName);
  final String propertyName = formatPropertyName(token.name());
 
@@ -699,14 +699,15 @@ private static CharSequence generateGroupDecoderProperty(
  className,
  propertyName,
  actingVersionGuard));
-
- return sb;
  }
 
- private CharSequence generateGroupEncoderProperty(
- final String groupName, final Token token, final String indent, final boolean isSubGroup)
+ private void generateGroupEncoderProperty(
+ final StringBuilder sb,
+ final String groupName,
+ final Token token,
+ final String indent,
+ final boolean isSubGroup)
  {
- final StringBuilder sb = new StringBuilder();
  final String className = formatClassName(encoderName(groupName));
  final String propertyName = formatPropertyName(groupName);
 
@@ -737,14 +738,11 @@ private CharSequence generateGroupEncoderProperty(
  generateGroupEncodePropertyJavadoc(indent + INDENT, token, className),
  className,
  propertyName));
-
- return sb;
  }
 
- private CharSequence generateDecoderVarData(final List<Token> tokens, final String indent)
+ private void generateDecoderVarData(
+ final StringBuilder sb, final List<Token> tokens, final String indent)
  {
- final StringBuilder sb = new StringBuilder();
-
  for (int i = 0, size = tokens.size(); i < size;)
  {
  final Token token = tokens.get(i);
@@ -791,14 +789,11 @@ private CharSequence generateDecoderVarData(final List<Token> tokens, final Stri
 
  i += token.componentTokenCount();
  }
-
- return sb;
  }
 
- private CharSequence generateEncoderVarData(final String className, final List<Token> tokens, final String indent)
+ private void generateEncoderVarData(
+ final StringBuilder sb, final String className, final List<Token> tokens, final String indent)
  {
- final StringBuilder sb = new StringBuilder();
-
  for (int i = 0, size = tokens.size(); i < size;)
  {
  final Token token = tokens.get(i);
@@ -841,8 +836,6 @@ private CharSequence generateEncoderVarData(final String className, final List<T
 
  i += token.componentTokenCount();
  }
-
- return sb;
  }
 
  private void generateDataDecodeMethods(
@@ -1453,7 +1446,7 @@ private CharSequence generateEnumValues(final List<Token> tokens)
  {
  final Encoding encoding = token.encoding();
  final CharSequence constVal = generateLiteral(encoding.primitiveType(), encoding.constValue().toString());
- sb.append(generateTypeJavadoc(INDENT, token));
+ generateTypeJavadoc(sb, INDENT, token);
  sb.append(INDENT).append(token.name()).append('(').append(constVal).append("),\n\n");
  }
 
@@ -1644,14 +1637,14 @@ else if (tokens.get(index).signal() == Signal.END_GROUP && --level < 0)
  private static CharSequence generateDeclaration(
  final String className, final String implementsString, final Token typeToken)
  {
- return String.format(
- "%s" +
-  "@SuppressWarnings(\"all\")\n" +
-  "public class %s%s\n" +
- "{\n",
- generateTypeJavadoc(BASE_INDENT, typeToken),
- className,
-  implementsString);
+ final StringBuilder sb = new StringBuilder();
+
+ generateTypeJavadoc(sb, BASE_INDENT, typeToken);
+ sb.append("@SuppressWarnings(\"all\")\n")
+ .append("public class ").append(className).append(implementsString).append('\n')
+ .append("{\n");
+
+ return sb.toString();
  }
 
  private void generatePackageInfo() throws IOException
@@ -1703,9 +1696,12 @@ private void generateMetaAttributeEnum() throws IOException
 
  private static CharSequence generateEnumDeclaration(final String name, final Token typeToken)
  {
- return
- generateTypeJavadoc(BASE_INDENT, typeToken) +
- "public enum " + name + "\n{\n";
+ final StringBuilder sb = new StringBuilder();
+
+ generateTypeJavadoc(sb, BASE_INDENT, typeToken);
+ sb.append("public enum ").append(name).append("\n{\n");
+
+ return sb.toString();
  }
 
  private CharSequence generatePrimitiveDecoder(
@@ -2614,11 +2610,9 @@ private CharSequence generateEncoderFlyweightCode(final String className, final
  CodecType.ENCODER, className, token, wrapMethod + wrapAndApplyMethod, mutableBuffer);
  }
 
- private CharSequence generateEncoderFields(
- final String containingClassName, final List<Token> tokens, final String indent)
+ private void generateEncoderFields(
+ final StringBuilder sb, final String containingClassName, final List<Token> tokens, final String indent)
  {
- final StringBuilder sb = new StringBuilder();
-
  Generators.forEachField(
  tokens,
  (fieldToken, typeToken) ->
@@ -2654,14 +2648,10 @@ private CharSequence generateEncoderFields(
  break;
  }
  });
-
- return sb;
  }
 
- private CharSequence generateDecoderFields(final List<Token> tokens, final String indent)
+ private void generateDecoderFields(final StringBuilder sb, final List<Token> tokens, final String indent)
  {
- final StringBuilder sb = new StringBuilder();
-
  Generators.forEachField(
  tokens,
  (fieldToken, typeToken) ->
@@ -2696,8 +2686,6 @@ private CharSequence generateDecoderFields(final List<Token> tokens, final Strin
  break;
  }
  });
-
- return sb;
  }
 
  private static void generateFieldIdMethod(final StringBuilder sb, final Token token, final String indent)

sbe-tool/src/main/java/uk/co/real_logic/sbe/generation/java/JavaUtil.java

@@ -252,22 +252,22 @@ public static String generateLiteral(final PrimitiveType type, final String valu
  /**
  * Generate the Javadoc comment header for a type.
  *
+ * @param sb to append to.
  * @param indent level for the comment.
  * @param typeToken for the type.
- * @return a string representation of the Javadoc comment.
  */
- public static String generateTypeJavadoc(final String indent, final Token typeToken)
+ public static void generateTypeJavadoc(
+ final StringBuilder sb, final String indent, final Token typeToken)
  {
  final String description = typeToken.description();
  if (null == description || description.isEmpty())
  {
- return "";
+ return;
  }
 
- return
- indent + "/**\n" +
- indent + " * " + description + '\n' +
- indent + " */\n";
+ sb.append(indent).append("/**\n")
+ .append(indent).append(" * ").append(description).append('\n')
+ .append(indent).append(" */\n");
  }
 
  /**